12780942091 has 4 divisors (see below), whose sum is σ = 13532762232. Its totient is φ = 12029121952.

The previous prime is 12780942077. The next prime is 12780942143. The reversal of 12780942091 is 19024908721.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 12780942091 - 2⁷ = 12780941963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12780942001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 375910045 + ... + 375910078.

It is an arithmetic number, because the mean of its divisors is an integer number (3383190558).

Almost surely, 2^12780942091 is an apocalyptic number.

12780942091 is a deficient number, since it is larger than the sum of its proper divisors (751820141).

12780942091 is an equidigital number, since it uses as much as digits as its factorization.

12780942091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 751820140.

The product of its (nonzero) digits is 72576, while the sum is 43.

The spelling of 12780942091 in words is "twelve billion, seven hundred eighty million, nine hundred forty-two thousand, ninety-one".